Need help with a clutch dimension

[BigBlock67]

I'm changing the automatic back to a stick. This time it's an NV4500 behind the 402 with the manual clutch linkage instead of the hydraulic. I'm making the lower arm for the Z-bar and need to know how far the clutch arm sticking out of the bellhousing moves when the clutch pedal is pushed in. I still have the original linkage under the dash and it moves 1 9/16 in. I checked a 78 chevy 3/4 ton and it only moved 1 1/8 in. My concern is I don't want to over extend the fingers on the pressure plate. This truck is a 67 3/4 ton that was originaly a 283 4-speed. If somebody could measure theirs it would be a big help.